From my experience this is more of a skill based matchup. Your pix works well against his voidlings but Malz's damage will never compare to yours and his spell-shield makes this match up sometimes difficult.

Introduction

Runes Reforged

Sorcery is the perfect primary path, with Resolve or Domination being the best secondary path. These two paths combined include the most optimal utility and damage enhancements for Lulu's kit.

Right now I am running Sorcery and Domination.

SORCERY

1. Summon Aery:Your attacks and abilities send Aery to a target, damaging enemies or shielding allies.
Lulu is all about being a lane bully and peeling. Aery will assist her alongside Pix to put out the most damage possible. This will help with laning pressure and Lulu will become even more of a bully than before. Aery also aids your teammates with a shield when targeted with your E.

2. The Ultimate Hat:Your ultimate's cooldown is reduced. Each time you cast your ultimate, its cooldown is further reduced.
This is pretty self explanatory. The lower cooldown your ult is, the more you can use it to save allies/yourself and make plays.

3. Transcendence:Gain 10% CDR when you reach level 10. Excess CDR becomes AP or AD, adaptive.
Cooldown reduction is very crucial when it comes to supports. The more often your spells are up means you can peel a lot more. The excess CD turns into more AP which means your abilities are stronger on both ally cast and enemy cast.

Many options with your 4th choice:4. Scorch:Your first ability hit every 20s burns champions.
This option is best if you are sure you plan on bullying and harassing in lane often.4. Waterwalking:Gain MS and AP or AD, adaptive in the river.
This option is best when you plan on roaming frequently.4. Gathering Storm:Gain increasing amounts of AD or AP, adaptive over the course of the game.
This option is best if you plan on having a late game comp, or just a long game in general. Its also a good choice if you are VS a hard matchup bot lane and you cant poke as much as you want to.

DOMINATION

1. Cheap ShotDamaging champions with impaired movement or actions deals 12-30 bonus true damage (based on level.)
Cheap shot is for the extra damage in laning phase and works even better if your ADC also has any type of CC. Your Q, W, and R will proc this rune.

OR

1. Zombie WardAfter killing a ward, a friendly Zombie Ward is raised in it place. When your wards expire, they also reanimate as Zombie Wards.
Vision can solely win you games. Having vision of the enemy team can prevent you from getting picked off and ganked. If you have vision of the enemy you will be able to play more aggressive in lane and/or go for certain objectives without hesitation.

2. Ingenious HunterGain 10% Active Item CDR plus an additional 6% per Bounty Hunter stack (includes trinkets).
This rune is one of the best to take on supports right now because of all the actives you are in control of: Locket, Redemption, Frost Queen's Claim, Trinket, etc. I have found this very useful recently especially for clearing vision hence the CDR on your trinket.

RESOLVE

1. Revitalize:Heals and shields are 5% stronger and increased by an additional 10% on low health targets.
Revitalize strengthens your E along with your other shields and heals from items; Locket, Athenes, and Redemption.

2. Font of Life:Impairing the movement of an enemy champion marks them. Your allies heal when attacking champions you've marked.
This rune works when you Q or W an enemy. It also works if the enemy is affected by your ultimate's knock-up and slow. Font of Life also corresponds with the rune Revitalize.

Lulu, in my opinion, is the most diverse champion in League of Legends when it comes to builds, skill sequence, runes, etc. That being said, a lot of different choices can be made in runes. The runes stated above are what works for me. Have fun and do whatever you please.

Skill Sequence

Every Lulu player is different, and you can do whatever fits your style!
For me, I love going E, W, Q. (skill order and maxing)

Your E is point click damage so lvl 1 poking is quite easy. Its also good for out-trading since you can shield damage taken.
I also like going W for lvl 2 if the enemies will be engaging on us. If i know i can put more damage out without consequence, I will go Q lvl 2.

Items

SPELLTHIEFS vs ANCIENT COIN
Spellthiefs gives you your gold income from using your abilities and auto attacks on enemies and towers. Lulu is a great lane bully, so building this item and using her kit correctly is the best way to maximize your gold income.
If you feel that your laning is going to be more passive and you won't be able to poke as much, then going Coin will be way more efficient. I find going this item is better vs lanes that are more aggressive than yourself.

RUBY SIGHSTONE vs EYE OF THE WATCHERS
Ruby Sighstone has a unique passive that reduces your active cooldowns by 20%. This item goes great with Redemption, Locket, and Frost Queen's, since they are all items that have actives bound to them.
Eye of the Watchers is a better choice when you have a strong lead in the early game, because it gives you plenty of snowbally stats such as 25 AP and 10% CD. Since you probably wont even get into the late game to finish building all your active items, Eye of the Watchers is better for an early game/early win situation.

BOOTS
When it comes to boots, it really is your preference. Although, I highly recommend rushing lucidity for the early CDR on your abilities and the CDR on your summoner spells, Ninja Tabis if you are vs a heavy ad comp, or mobis if you plan to roam often.

REDEMPTION & LOCKET
Both Redemption and Locket are core items for Lulu. If your team is getting bursted easily, then rushing Locket before Redemption is the better choice because of the instant shield it applies. If your team tends to have long or extended fights, then a Redemption rush will be more efficient.

ARDENT CENSOR
Because you are shielding so much this item is core on Lulu and great to build for your ADC. It provides your ADC with 10%-30% attack speed and their auto attacks will deal an additional 5-20 on hit magic damage for 6 seconds. Your shields/heals also are 10% stronger(This applies to your other core items aswell; Redemption & Locket) and you gain 8% movement speed.

Abilities

As lulu, you want to be on top of your ADC/backline the whole game. Your job is to protect the team, not engage.

GLITTERLANCE (Q):
Nothing really to explain here. Use your Q for poke/harass and slowing the enemies.

WHIMSY (W):
"When do I use Polymorph over buffing my ADC with Whimsy(W)?" IMO and experience, you will be using your W on enemy cast a lot more often than buffing your ADC. You want to polymorph whoever gets on top of your ADC or the back line. When using your W, enemies will be polymorphed for a while (1.25 / 1.5 / 1.75 / 2 / 2.25), and can be killed before they can come out of it. The only case you will be using Whimsy on your allies, is when you are chasing or if there is no one diving your backline, to provide your ADC/Carry with attack speed (25 / 30 / 35 / 40 / 45% and movement speed.

HELP, PIX (E):
Your E is mainly going to be used for shielding and buffing your allies. Although in some cases, your E on enemy cast is VERY helpful. Your E on enemy cast gives VISION. This is strong when you are playing against a Twitch, Vayne, etc. If you can get your E off before they go into stealth, they can easily be killed/chased since they are seen. Your E also can also extend the length of your Q. For example, if you E a minion ahead of you and then use Q, 1 part of your Q will be casted from that minion instead of your character model.

WILD GROWTH (R):
Your ult provides a huge knock up to anyone around the ally champion you have ulted. It also grants your ally 300 / 450 / 600 (+ 50% AP) bonus health and slows nearby units by 30 / 45 / 60%. You want to use this to either save whoever jumps on your back line or it can be used on your engager for a knock up.
For example, if a Lee Sin Q's your ADC, you want to ult your ADC as soon as he reaches them to knock him up to prevent him from actually touching them. You can also use your ult on maybe a Malphite engage. Malphite hits a 4 man ult, and you ult right after. Lulu R does a great job chaining CC.